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Managed Investment Entities - Narrative (Details) $ in Millions | 1 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2018 USD ($) collateralizedloanobligation | Sep. 30, 2019 USD ($) collateralizedloanobligation | Sep. 30, 2018 USD ($) collateralizedloanobligation | Dec. 31, 2018 USD ($)
Variable Interest Entity [Line Items] |  |  |  |
Percentage of investment of most subordinate debt tranche, Minimum |  | 15.00% |  |
Percentage of investment of most subordinate debt tranche, Maximum |  | 60.90% |  |
Number of collateralized loan obligation entities | collateralizedloanobligation |  | 11 |  |
Number of collateralized loan obligation entities formed during the period | collateralizedloanobligation | 1 |  |  |
Proceeds received by subsidiaries related to sales and redemptions of managed investment entities liabilities |  |  | $ 45 |
Number of collateralized loan obligation entities substantially liquidated, during the period | collateralizedloanobligation |  |  | 1 |
Difference between aggregate unpaid principal balance and fair value of CLOs' fixed maturity investments |  | $ 165 |  | $ 232
Difference between aggregate unpaid principal balance and carrying value of CLOs' debt |  | 154 |  | 241
Carrying amount of CLO loans in default |  | 8 |  |
Aggregate unpaid principal balance of variable interest entity loans in default |  | 21 |  | 0
Available for sale (AFS) fixed maturities |  | 45,503 |  | 41,997
Variable interest entity, primary beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Aggregate fair value of investment in collateralized loan obligations |  | 179 | $ 191 | 188
New Collateralized Loan Obligation Entities |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Face value of liabilities issued by managed investment entities on issuance date | $ 463 |  |  |
Face amount of managed investment entities liabilities purchased by subsidiaries at issuance date | $ 31 |  |  |
Subordinated Debt Obligations | Variable interest entity, primary beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Aggregate fair value of investment in collateralized loan obligations |  | 116 |  |
Maximum |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Proceeds received by subsidiaries related to sales and redemptions of managed investment entities liabilities |  | 1 |  |
Collateralized loan obligations |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Available for sale (AFS) fixed maturities |  | 4,314 |  | 4,278
Collateralized loan obligations | Managed by third parties |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Available for sale (AFS) fixed maturities |  | $ 4,310 |  | $ 4,280

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